Asthma

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This page is primarily targeted at the issue of chronic asthma in pediatric patients in the outpatient setting (and does not discuss acute exacerbations nor patients with severe persistent asthma). Its ambitious goal is to summarize asthma in roughly one page (I failed at that) while providing links to other resources for more details. Please email suggestions to Tai Roe.

General
  • A chronic inflammatory disorder of the airways, with both an environmental and genetic basis
  • Airway inflammation leads to airway hyperresponsiveness, airflow limitation
  • The second most common chronic disease of childhood (after dental caries)
  • Between 5-25%, on the rise world-wide, unknown why.

Risk factors
  • Family history (LR factor of 2.5 per parent who has Asthma)
  • Part of triad with eczema and allergic rhinitis
  • History of wheezing before age 3, bronchiolitis or "colds that persist"
  • Environmental exposures (smoke, molds, pets, living near freeways/roadways, etc.)
  • Early respiratory infections (e.g. RSV before age 1)
  • Growing up with multiple pets offers some protection

Symptoms
  • Cough
  • Wheezing
  • Shortness of breath - or trouble getting your breath after exercise
  • In infants, also grunting, poor suck, poor feeding, tachypnea

History
  • Episodic, recurrent pattern of symptoms
  • Often worse at night, may awaken patient
  • Triggered by exercise, respiratory infections, pets, mold, dust mites, cockroaches, smoke, pollen, weather changes, airborne chemicals, emotional stress, menstrual cycles
  • Inquire about prior hospitalizations, ER visits, frequency and severity of exacerbations, prior use of medicines, missing school

Diagnosis
  • Risk factors?
  • Recurrent symptoms?
  • Pattern: Nighttime? Triggers?
  • Spirometry is recommended in children >= 5: look for increase in FEV1 from baseline after giving short-acting bronchodilator
  • Except in significant exacerbations, physical exam may be unremarkable (but can look for eczema, rhinitis)
  • Differential diagnosis is very long, but remember, asthma is common, zebras are not

Testing
  • Spirometry in kids >= 5
  • Chest X-ray not routinely recommended unless suspecting other conditions such as foreign body aspiration, PNA, heart disease, pneumothorax, etc
  • Peak flows are not reliable for diagnosis. Good to follow response to therapy if tracked.

Classification - Nocturnal, Exercise Induced or Allergic
Severity - Intermittent or Persistent (mild, mod, severe)
  • This "Rules of 2" is a fairly simple, easy way to remember a much more complicated classification system
  • A child has "Persistent" asthma if the child meets one of the "Rules of 2":
    • Using more than 2 canisters of albuterol/levalbuterol per year
    • Having symptoms or using albuterol/levalbuterol more than 2 times per week
    • Having nighttime cough more than 2 times per month
    • Having significant exacerbations 2 or more times per year
  • Otherwise, the child is considered to have "intermittent" asthma

Treatment
  • Patient education is key, e.g. chronicity, role of controller medicine, spacer (and its proper use), removal of environmental triggers (Smoke, animal dander, down pillows), give flu vaccines, Rules of 2. Consider using Asthma Action Plans (available in English, Spanish and Chinese, with provider instructions), mostly for patients with moderate or severe persistent asthma
  • If asthma is definitely "Intermittent", i.e. not persistent, can use just short-acting bronchodilator (albuterol/levalbuterol).
  • For everyone else, i.e. "Persistent" asthma, the single most important medicine is an inhaled corticosteroid (ICS) used as a "controller" medicine (they reduce risk of death!) prescribed with a spacer
    • Start with low-dose ICS
    • See patient back in 2 - 4 weeks
    • If symptoms not controlled, step up treatment, and see back in 2 - 4 weeks, using:
      • Medium-dose ICS (probably preferred) QVAR covered, comes in 40 and 80 strengths
      • If older than 5, alternative is low-dose ICS + long-acting beta agonist (LABA), e.g. salmeterol or formoterol, available in Advair or Symbicort. Do not use LABA alone.
      • If older than 1, alternative is low-dose ICS + leukotriene receptor antagonist (LTRA), e.g. montelukast or zafirlukast
    • If symptoms still not controlled, this patient may have severe, persistent asthma and may need referral
    • Rinse mouth after use
    • Most of our clinics can dispense Peak Flow Meters -- make a game out of "getting the best # you can"
  • Some Consider starting "higher" to get quick control and then stepping down as long as control is good.
  • Consider immunotherapy (i.e. allergy injections) if clear relationship between symptoms and allergen exposure)
  • Treat co-existing allergic rhinitis (nasal saline rinses and nasal steroids)
  • Kids may need duplicate Rxs and provider's note indicating they can use their medicines at school.

Other resources
2007 Expert Panel Report from National Heart Lung and Blood Institute (available there is full document of 440 pages!)

Global Initiative for Asthma (pharmaceutical supported) has some shorter guidelines

Asthma Guidelines CCHP 2007.pdf

2009 review article on "Practical Management of Asthma"

This page has been edited 26 times. The last modification was made by - tairoe tairoe on Jan 24, 2011 8:01 am